CVEvulnerability
CVE-2026-40686
5.3 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-04-30
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 3.7 LOW — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
- CVSS 3.1 ([email protected])
- 5.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Weaknesses
- CWE-125
Description
In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.
Affected configurations
• exim exim (< 4.99.2)
Related
Weakness · CWE (1)
- CWE-125 Out-of-bounds Read weakness
References
- https://code.exim.org/exim/exim/commit/f2570bde16fb4d4a1242ff363a4c4eecf6372efc Patch
- https://exim.org/static/doc/security/CVE-2026-40686.txt Broken Link
- https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40686.assessment Vendor Advisory
- https://www.openwall.com/lists/oss-security/2026/04/30/21 Mailing List, Third Party Advisory